Role of Humified Organic Matter in Herbicide Adsorption

Organic matter is the soil constituent most often associated with herbicide adsorption. Structural diversity makes humified organic material an ideal substrate for the adsorption of many pesticides, but variability in composition and distribution in situ complicates interpretation of its quantitative effect on adsorption. Variability in the adsorption distribution coefficient (KD) of a herbicide among soils often is due to differences in organic matter content and can be reduced by adjusting KDfor soil organic carbon content and computing the organic carbon partition coefficient (Koc). Koccan be estimated from the octanol-water partition coefficient (Kow) of organic compounds, but the correlation weakens as compound polarity increases. Kocalso can be correlated with aqueous solubility if a correction is made for the melting point of compounds that are solids at 25 C. Relative adsorption can be estimated from parachor and molecular connectivity indices; but corrections are needed for polar compounds, and correlations with KDor Kochave been variable. Such predictive methods may be useful for broad classification purposes, but accurate extrapolation generally requires site-specific adsorption measurements. Empirical models which accommodate the multiple regression of organic matter content and other soil properties such as clay content, pH, and cation exchange capacity on herbicide adsorption can increase accuracy, but interpretation may be restricted to a small number of sites.

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Organic carbon determination in histosols and soil horizons with high organic matter content from Brazil

Scientia Agricola ◽

10.1590/s0103-90162006000200012 ◽

2006 ◽

Vol 63 (2) ◽

pp. 187-193 ◽

Cited By ~ 15

Author(s):

Marcos Gervasio Pereira ◽

Gustavo Souza Valladares ◽

Lúcia Helena Cunha dos Anjos ◽

Vinícius de Melo Benites ◽

Ademar Espíndula Jr. ◽

...

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Organic Matter Content ◽

Analysis Data ◽

Matter Content ◽

Organic Soils ◽

Organic Carbon Content ◽

Muffle Furnace ◽

Soil Taxonomy ◽

High Organic Carbon Content

Soil taxonomy systems distinguish mineral soils from organic soils based on the amount of soil organic carbon. Procedures adopted in soil surveys for organic carbon measurement are therefore of major importance to classify the soils, and to correlate their properties with data from other studies. To evaluate different methods for measuring organic carbon and organic matter content in Histosols and soils with histic horizons, from different regions of Brazil, 53 soil samples were comparatively analyzed by the methods of Walkley & Black (modified), Embrapa, Yeomans & Bremner, modified Yeomans & Bremner, muffle furnace, and CHN. The modified Walkley & Black (C-W & B md) and the combustion of organic matter in the muffle furnace (OM-Muffle) were the most suitable for the samples with high organic carbon content. Based on regression analysis data, the OM-muffle may be estimated from C-W & B md by applying a factor that ranges from 2.00 to 2.19 with 95% of probability. The factor 2.10, the average value, is suggested to convert results obtained by these methods.

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The color of refractory organic carbon

BSGF - Earth Sciences Bulletin ◽

10.1051/bsgf/2018008 ◽

2018 ◽

Vol 189 (2) ◽

pp. 9 ◽

Cited By ~ 1

Author(s):

Maxime Debret ◽

Yoann Copard ◽

Antonin Van Exem ◽

Geneviève Bessereau ◽

Frank Haeseler ◽

...

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Carbon Content ◽

Anthropogenic Activities ◽

Organic Matter Content ◽

Matter Content ◽

Mineral Matter ◽

Organic Carbon Content ◽

Fast Method ◽

Wide Range

Organic matter studies find an echo within different topics such as biogeochemical cycles, processes occurring in continental surfaces, anthropogenic activities, climate science, earth and planetary sciences, etc. Today’s challenges include finding and developing the most appropriate method(s) supporting the differentiation and characterisation of various types of recalcitrant organic matter in modern environments. In this study, we focus on combustion residues and coals as these two types of organic matter contain a significant amount of so-called recalcitrant organic carbon (black carbon and fossil organic carbon). Both these materials are ubiquitous, broadly stem from the same living organisms and have similar polyaromatic structures. In this respect, we tested a spectrophotometry method, classically used for sedimentology, as a very fast method for preliminary investigations. Analyses were performed with a wide range of standards and referenced samples. The results discriminate three different spectral signatures related to the degree of transformation of organic matter related to the degree of aromaticity (i.e. carbonisation). Using calibration curves, total organic carbon content can be estimated in experimental mixes with mineral matter and in a real context using subsurface sample (Gironville 101 borehole, Paris Basin, France). This method has particularly high sensitivity to very low organic matter content and is shown to be promising for a rapid evaluation of the organic carbon content.

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Soil attributes related to water repellency and the utility of soil survey for predicting its occurrence

Soil Research ◽

10.1071/sr9941109 ◽

1994 ◽

Vol 32 (5) ◽

pp. 1109 ◽

Cited By ~ 64

Author(s):

RJ Harper ◽

RJ Gilkes

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Water Drop ◽

Organic Matter Content ◽

Clay Content ◽

Soil Surface ◽

Water Repellency ◽

Soil Survey ◽

Organic Carbon Content ◽

Penetration Time

The incidence and severity of water repellency was related to five soil class (FC I-V), based on the field texture and dry consistence of the soil surface horizons, derived from a soil survey near Jerramungup, Western Australia. Water repellency was most severe on the FC I soils (median clay content 1.5%), with 66% of samples having water repellency based on the water drop penetration time (WDPT) test >10 s. Corresponding values for the FC II and III soils (2.5%, 4.0% clay) were 37% and 20%. Water repellency did not occur on the most clayey FC IV (8.1% clay) and FC V (22.1% clay) soils. Following stratification of Ap horizon soils by 1% increments of clay content, highly significant linear relationships occurred between log [water drop penetration time (WDPT)] and log [organic carbon (OC)] for the 1-2, 2-3 and 3-4% clay classes, these respectively explaining 50, 35 and 37% of the variation in water repellency. The role of organic carbon in promoting water repellency decreases markedly with increasing clay content, with WDPT being proportional to OC4.5, OC3.9 and OC3.0 for each of these clay classes. A multivariate relationship using measures of amorphous iron, clay and organic matter explained 63% of the variation in water repellency, and this multivariate dependency provides an explanation of the poor bivariate relationships between either clay or organic carbon content and water repellency reported in previous studies. There is a strong geomorphic control of the clay content in the soil surface horizons. Given the effect that clay content has on water repellency, the susceptibility of soils to water repellency can be mapped across farms, with the actual expression of water repellency depending on soil organic matter content, and hence land use. Such discrimination will allow the prediction of water erosion hazard and identify soils requiring ameliorative treatments.

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Spatial distribution of organic matter in the surface sediments of Ubatuba Bay (Southeastern - Brazil)

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652003000100009 ◽

2003 ◽

Vol 75 (1) ◽

pp. 77-80 ◽

Cited By ~ 58

Author(s):

LETICIA BURONE ◽

PABLO MUNIZ ◽

ANA MARIA S. PIRES-VANIN ◽

MARCELO RODRIGUES

Keyword(s):

Organic Matter ◽

Spatial Distribution ◽

Organic Carbon ◽

Carbon Content ◽

Pearson Correlation ◽

Organic Matter Content ◽

Matter Content ◽

Southeastern Brazil ◽

Organic Carbon Content ◽

Fast Evaluation

Analyses of organic matter content, organic carbon, nitrogen, sulfur and granulometric variables were performed on 101 surface sediment samples from Ubatuba Bay in order to investigate the spatial distribution of organic matter, its origin and the relationships among its components. The samples were obtained with a manual corer, from water depths between 1 and 15m during 5 cruises of the R/V "Veliger II'', two months apart. Pearson correlation, regression and Principal Component Analysis (PCA) statistical methods were used to analyze the data. Strong correlations between organic matter and fine sediment fractions were obtained. The PCA revealed at least two main sample groups that reflect the different environmental conditions prevalent in the bay. There is a simple linear relationship between organic carbon content and the organic matter content determined by the calcination technique. Taking into account that the analysis of organic matter content is less expensive and less time consuming than the analysis of organic carbon, the present method of estimation can be useful when fast evaluation of the organic carbon content is needed for samples from similar environments.

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Long-Term Carbon Accumulation in Temperate Swamp Soils: A Case Study from Greenock Swamp, Ontario, Canada

10.21203/rs.3.rs-1044474/v1 ◽

2021 ◽

Author(s):

Emily Dazé ◽

Eunji Byun ◽

Sarah A Finkelstein

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Soil Carbon ◽

Organic Matter Content ◽

Matter Content ◽

Carbon Accumulation ◽

Organic Carbon Content ◽

Thuja Occidentalis ◽

Wetland Types

Abstract Wetlands that develop peat are a globally significant pool of soil carbon. While some wetland types such as bogs and fens are well characterized by the consistent development of carbon-rich peat, swamps soils are more variable both in terms of their carbon densities and accretion rates. Subcategorizing swamps by forest type may be a useful way of understanding this variability. Here we provide a case study of carbon accumulation in two distinct forest stands of Greenock Swamp located in the Great Lakes – St Lawrence mixed forest region in Bruce County, Ontario, Canada: an Acer - Fraxinus (maple-ash) dominant stand (i.e., broad-leaved swamp) and a Thuja occidentalis (cedar) dominant stand (i.e., needle-leaved swamp). Organic matter and organic carbon contents were analyzed among seven Acer - Fraxinus soil cores and one Thuja occidentalis core collected from Greenock Swamp. The Acer - Fraxinus cores had peat depths ranging from 18-60 cm with a mean organic matter content of 54% and an organic carbon content of 34% of dry mass. The Thuja occidentalis swamp core had at least 4 m of almost homogeneous peat with a mean organic matter content of 89%. Radiocarbon dating indicates that the Acer - Fraxinus swamp accumulates peat episodically whereas the Thuja occidentalis swamp showed continuous peat accumulation since the Middle Holocene. Overall, both broad-leaved and needle-leaved swamps have important soil carbon stocks, and are prevalent wetland types in middle latitudes. Both need to be considered to fully represent the carbon pools and potential sink of temperate wetlands.

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Factors Affecting Microbial Formation of Nitrate-Nitrogen in Soil and Their Effects on Fertilizer Nitrogen Use Efficiency

The Scientific World JOURNAL ◽

10.1100/tsw.2001.308 ◽

2001 ◽

Vol 1 ◽

pp. 122-129 ◽

Cited By ~ 7

Author(s):

Alan Olness ◽

Dian Lopez ◽

David Archer ◽

Jason Cordes ◽

Colin Sweeney ◽

...

Keyword(s):

Organic Matter ◽

Decision Aid ◽

Pore Space ◽

Organic Matter Content ◽

Clay Content ◽

Matter Content ◽

N Fertilizer ◽

Nitrate N ◽

Soil Clay ◽

Soil Clay Content

Mineralization of soil organic matter is governed by predictable factors with nitrate-N as the end product. Crop production interrupts the natural balance, accelerates mineralization of N, and elevates levels of nitrate-N in soil. Six factors determine nitrate-N levels in soils: soil clay content, bulk density, organic matter content, pH, temperature, and rainfall. Maximal rates of N mineralization require an optimal level of air-filled pore space. Optimal air-filled pore space depends on soil clay content, soil organic matter content, soil bulk density, and rainfall. Pore space is partitioned into water- and air-filled space. A maximal rate of nitrate formation occurs at a pH of 6.7 and rather modest mineralization rates occur at pH 5.0 and 8.0. Predictions of the soil nitrate-N concentrations with a relative precision of 1 to 4 μg N g–1of soil were obtained with a computerized N fertilizer decision aid. Grain yields obtained using the N fertilizer decision aid were not measurably different from those using adjacent farmer practices, but N fertilizer use was reduced by >10%. Predicting mineralization in this manner allows optimal N applications to be determined for site-specific soil and weather conditions.

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A small rainfall simulator for the determination of soil erodibility.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v35i3.16735 ◽

1987 ◽

Vol 35 (3) ◽

pp. 407-415 ◽

Cited By ~ 4

Author(s):

A. Kamphorst

Keyword(s):

Organic Matter ◽

Soil Conservation ◽

Standard Procedure ◽

Organic Matter Content ◽

Clay Content ◽

Matter Content ◽

Soil Erodibility ◽

Rainfall Simulator ◽

Highly Sensitive

A small rainfall simulator is described, which can be used in the field as well as in the laboratory for the determination of infiltration and erosion characterisitcs of soils. It is particularly suitable for soil conservation surveys, as it is light to carry and easy to handle in the field. A description is given of a standard procedure for the determination of topsoil erodibilities in the field and some results are presented. The method appears to be highly sensitive to soil properties influencing soil erodibility, such as clay content, organic matter content and soil pH. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Impacts of vinasse and methods of sugarcane harvesting on the availability of K and carbon stock of an Argisol

Revista CERES ◽

10.1590/0034-737x201663010013 ◽

2016 ◽

Vol 63 (1) ◽

pp. 95-102 ◽

Cited By ~ 1

Author(s):

Claudinei Alberto Cardin ◽

Carlos Henrique dos Santos ◽

Marcos Antonio Escarmínio

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Carbon Stock ◽

Organic Matter Content ◽

Matter Content ◽

Total Carbon ◽

Native Forest ◽

Mean Values ◽

Tropical Regions ◽

Soil Carbon Stock

ABSTRACT Soils of tropical regions are more weathered and in need of conservation managements to maintain and improve the quality of its components. The objective of this study was to evaluate the availability of K, the organic matter content and the stock of total carbon of an Argisol after vinasse application and manual and mechanized harvesting of burnt and raw sugarcane, in western São Paulo.The data collection was done in the 2012/2013 harvest, in a bioenergy company in Presidente Prudente/SP. The research was arranged out following a split-plot scheme in a 5x5 factorial design, characterized by four management systems: without vinasse application and harvest without burning; with vinasse application and harvest without burning; with vinasse application and harvest after burning; without vinasse application and harvest after burning; plus native forest, and five soil sampling depths (0-10 10-20, 20-30, 30-40, 40-50 cm), with four replications. In each treatment, the K content in the soil and accumulated in the remaining dry biomass in the area, the levels of organic matter, organic carbon and soil carbon stock were determined. The mean values were compared by Tukey test. The vinasse application associated with the harvest without burning increased the K content in soil layers up to 40 cm deep. The managements without vinasse application and manual harvest after burning, and without vinasse application with mechanical harvesting without burning did not increase the levels of organic matter, organic carbon and stock of total soil organic carbon, while the vinasse application and harvest after burning and without burning increased the levels of these attributes in the depth of 0-10 cm.

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Constant current chronopotentiometric stripping characterisation of organic matter in seawater from the northern Adriatic, Croatia

Environmental Chemistry ◽

10.1071/en13122 ◽

2014 ◽

Vol 11 (2) ◽

pp. 158 ◽

Cited By ~ 4

Author(s):

Slađana Strmečki ◽

Jelena Dautović ◽

Marta Plavšić

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Seasonal Changes ◽

Electrochemical Techniques ◽

Organic Matter Content ◽

Matter Content ◽

Constant Current ◽

Po River ◽

Northern Adriatic ◽

Catalytically Active

Environmental context We determined seasonal changes in the organic matter content of the northern Adriatic with newly applied electrochemical techniques able to measure catalytically active organics. The inflow of the Po River and its nutrient load are responsible for the observed changes in the type and concentrations of organic matter in the area. Abstract Catalytically active polysaccharides (Cat PSs) and nitrogen-containing polymeric organic material (N-POM) were determined in seawater from the northern Adriatic station ST101. Catalytically active organics were measured by applying electrochemical methods of adsorptive transfer chronopotentiometric stripping with medium exchange and chronopotentiometric stripping in unmodified seawater. Their concentrations were expressed in milligrams per cubic decimetre–3--> of equivalents of the model calibrating substances, polysaccharide xanthan and protein human serum albumin. The optimal electroanalytical conditions for determination of Cat PSs in seawater were evaluated and defined. Seasonal changes of Cat PSs and N-POM were observed during the period 2011–2013. The highest values were determined in the spring–summer period and the lowest in winter. Cat PSs and N-POM were present in both the dissolved and particulate organic carbon fractions. Cat PSs and N-POM showed a statistically significant positive correlation with the concentrations of surface-active substances. A weak but statistically significant correlation was found between Cat PSs and dissolved organic carbon concentrations. Copper complexing capacities in the period 2011–2013 were in the range of 41–130nmoldm–3.

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